Binary sizes kill the assumption that it would be possible to use in embedded development. An unpredictable GC makes it impossible to use for realtime work.

For both you need:

   * An understanding of what kind of code will be generated
   * Predictable, and hopefully verified, GC
   * Reasonable binary sizes
   * Very good tree shaking

Currently the only things I've seen used for realtime developmend have been C, C++, Rust, raw assembly, and LISP. LISP and raw assembly are dead now. Rust is just starting and has a lot of progress to be made. C++ is showing some reasonable improvements. C is C.

If Scala Native could deliver on small binary sizes, "0 runtime" like Rust, and a way embed inline assembly like instructions then it would be a winner.

But how much predictability can you get in presence of garbage collection? Granted, the JIT can also be an element of surprise that is out of the picture with AOT and the statically linked GC can never be configured differently from what you expect, but it's still garbage collection and not Rust or a C.

Is this actually the case? I'd assume that Scala has the same dynamic nature as Java, and so AOT won't be able to convert dynamic dispatch to static as frequently.